Delete file in blender python script
That's right os.remove() is the way to go, on Unix (Linux and OSX too) and Windows. See this answer on stackoverflow

That error likely occurs because you are calling os.remove(some_file_path) where:


some_file_path isn't set at that moment in time   
or the filepath can't be resolved by os.remove().   


Try printing the value of some_file_path just ahead of calling os.remove(), most likely you'll either get an empty string or some modified path.



See this working example. 


This will add a panel to properties called Hello World Panel, 
it has a file selector and stores the filepath as a scene variable called some_identifier. 
The button 'Remove File' removes the file identified by scene property


code:

bl_info = {
    "name": "FILL ME IN",
    "author": "",
    "version": (0, 1),
    "blender": (2, 7, 6),
    "category": "3D View"
}

import os
import bpy
from bpy_extras.io_utils import ExportHelper


class WMFileRemover(bpy.types.Operator):
    bl_idname = "wm.remove_file"
    bl_label = "Remove File"

    def execute(self, context):
        fp = context.scene.some_identifier
        if fp:
            print('os.remove(', fp, ')')
            os.remove(fp)
        else:
            self.report({'ERROR'}, 'filepath is an empty string')
        return {'FINISHED'}


class WMFileSelector(bpy.types.Operator, ExportHelper):
    bl_idname = "something.identifier_selector"
    bl_label = "some folder"

    filename_ext = ""

    def execute(self, context):
        fdir = self.properties.filepath
        context.scene.some_identifier = fdir
        return{'FINISHED'}


class WMFilePanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'

    def draw(self, context):
        layout = self.layout
        scn = context.scene

        # ui
        col = layout.column()
        row = col.row(align=True)
        row.prop(scn, 'some_identifier', text='directory:')
        row.operator("something.identifier_selector", icon="FILE_FOLDER", text="")

        col = layout.column()
        col.label(scn.some_identifier)
        col.operator("wm.remove_file")


def register():
    bpy.types.Scene.some_identifier = bpy.props.StringProperty()
    bpy.utils.register_module(__name__)


def unregister():
    bpy.utils.unregister_module(__name__)
    del bpy.types.Scene.some_identifier